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51.
The rationale behind screening for asymptomatic coronary artery disease is that it may diagnose advanced disease that, while frequently without symptoms, may present for the first time as sudden death. Identifying significant coronary artery disease would enable intervention against risk factors and, if necessary, preventive revascularization. The most recent evidence shows that screening for coronary artery disease with resting electrocardiogram, exercise tolerance testing or electron-beam computerized tomography in low-risk patients does more harm than good, and should not be performed. This negative recommendation is based on the fact that the use of the aforementioned tests has a negative benefit-harm ratio, because the false-positive rate cancels out any benefit from the occasional detection of real disease, inducing a cascade of further testing (sometimes with angiography) and overdiagnosis of a disease that is not in fact present, with negative psychological and financial consequences, such as increased insurance premiums. We feel that the Portuguese Society of Cardiology should intervene with the institutions performing screening of coronary heart disease in asymptomatic patients, and recommend abandoning a practice that is of little use and, overall, harmful.  相似文献   
52.
Background Cystic dysraphic lesions of the cervical and upper thoracic region are rare and only a few series have been published about the topic. These malformations can be divided into categories that include both myelocystoceles and the so-called cervical meningoceles or myelomeningoceles.Methods A retrospective study of 18 patients was conducted.Results In 17 patients a squamous or a cicatricial epithelium of variable thickness covered the dome of the lesions, while the base was covered with full-thickness skin. In one case the skin was entirely normal. Four patients displayed associated CNS malformations and three more had systemic congenital anomalies. All patients underwent surgical exploration and the length of time between birth and surgery ranged from 6 h to 9 months. The most frequent surgical finding, seen in 14 patients, was a stalk connecting the dorsal surface of the spinal cord to the cyst. In three patients the findings were consistent with myelocystocele. Only in one case was a true meningocele found. Hydrocephalus and Chiari II malformation were not as consistently associated as in myelomeningoceles. Neurological signs and symptoms were not so marked as in myelomeningoceles and were found in the follow-up of four patients. In two of them there was a non-progressive deficit, probably expressing an imperceptible involvement of the nervous system in the first year of life. The histopathological findings were of three types: neuroglial stalks, fibrovascular stalks and myelocystoceles.Conclusions Cystic dysraphisms of the cervical and upper thoracic region differ clinically and structurally from meningomyelocele and have a more favorable outcome. We believe that these malformations have not been properly labeled and propose a classification based on the structures found inside the cyst.  相似文献   
53.
BACKGROUND: Identify risk factors for asthma in adolescents from S?o Paulo, Brazil. METHODS: total of 528 adolescents (141 asthmatics, 387 control subjects) from the ISAAC study (phase III) were submitted to a complementary questionnaire to evaluate risk factors, through response to questions regarding personal history, environment, and diet and an agreement to undergo the skin prick test (SPT) for aeroallergens. RESULTS: Positive SPT to at least one allergen occurred in 49.4% adolescents. The risk factors for asthma were: prematurity (OR: 3.84, 95% CI: 1.54-9.64), rhinitis (OR: 3.18, 95% CI: 1.71-5.91), positivity in the SPT (OR: 2.81, 95% CI: 1.48-5.32), eczema in characteristic skin-folds (OR: 2.86, 95% CI: 1.13-7.26), and an allergic mother (OR: 2.01, 95% CI: 1.02-3.93). The consumption of cooked vegetables was a protective factor for asthma (OR: 0.37, 95% CI: 0.18-0.79) CONCLUSIONS: Asthma is a multifatorial disease. An allergic mother, aeroallergen sensitization, rhinitis, eczema and prematurity were considered risk factors and the consumption of cooked vegetables was considered a protective factor for asthma in this population.  相似文献   
54.
An 8-year-old boy was seen with a cutaneous Ki-1 anaplastic, large cell lymphoma with multiple lesions. Some of the lesions showed spontaneous regression. During more than seven years of disease no systemic involvement was observed, but recurrent, self-healing lesions did appear. Histopathologic examination of five lesions revealed a variety of findings, from an inflammatory infiltrate to a highly anaplastic pattern. The neoplastic cells expressed Ki-1 and leukocyte common antigens. Ultrastructurally, those cells showed ruffled indentations. The differential diagnosis includes microvillous malignant lymphoma. The patient has had a four-year follow-up without relapses.  相似文献   
55.
Minocycline-associated hyperpigmentation is an uncommon side effect We report the case of a patient with pyoderma gangrenosum successfully treated with oral minocycline but complicated by marked hyperpigmentation in his pyoderma gangrenosum and acne scars. One of the clinical forms of minocycline hyperpigmentation includes dark-blue or black macules in depressed acne scars or other sites of skin inflammation; this pattern seems to be independent of the total cumulative dose and the skin process.  相似文献   
56.
The clinical and computerized tomographic (CT) findings in 10 patients with cerebral toxoplasmosis are reviewed. All patients with cerebral toxoplasmosis were homosexuals and/or intravenous drug users, and all patients had other manifestations of AIDS. Two presented with focal seizures, 4 presented with focal neurological deficit which progressively worsened, and 4 had evidence of diffuse neurological dysfunction (altered consciousness, generalized seizures). CT showed a single lesion in 3 patients and multiple lesions in 7 patients. Two patients had hypodense nonenhancing lesions(s). Eight patients had hypodense lesions with peripheral or nodular enhancement. The lesions were more commonly located in the cerebral hemispheres and subcortical gray matter nuclear masses (thalamus, basal ganglia). The finding of a hypodense lesion with a central slightly hyperdense noncalcified region that showed dense nodular homogeneous enhancement was quite characteristic of cerebral toxoplasmosis, but this pattern may also be seen in other neurological conditions including brain lymphomas.  相似文献   
57.
Aim of our study was to assess if the 2D-Echo transverse diameter of the left hepatic vein (LHV) obtained from the subcostal approach is correlated with invasive mean right atrial pressure (RAP). Thirty-two consecutive patients with acute myocardial infarction were studied by simultaneous 2D-Echo and right heart catheterization. LHV could be adequately imaged in 90% of patients. Mean RAP values at catheterization ranged from 0 to 15mmHg (mean 6±3.5 mmHg). A correlation was found between mean RAP and LHV diameter calculated after inspiration (r=0.81, SEE=1.54 mm, slope=0.71,p< 0.001) as well as after expiration (r=0.82, SEE=1.32mm, slope=0.62,p< 0.001) or during post-expiratory apnoea (r=0.85, SEE=1.3 mm, slope=0.71,p< 0.001). Moreover, percent increments of LHV diameter correlated well with percent changes of mean RAP during rapid infusion of 250–500 cc of saline in 4 patients (r=0.98,p< 0.001). Thus, the 2D-Echo LHV diameter is a feasible measurement that seems to correlate well with invasive mean RAP over a wide range of mean RAP values in patients with myocardial infarction; the changes in LHV diameter correlate well with the percent increase in central venous pressure obtained with saline infusion. Underestimation of invasive RAP occurs when mean RAP value exceeds 12 mmHg and can be explained by limited venous compliance. However these preliminary results suggest that this method may represent a valid alternative to obtain a non invasive estimate of mean RAP with 2D-Echocardiography.  相似文献   
58.
This consensus paper on behalf of the Study Group on Sports Cardiology of the European Society of Cardiology follows a previous one on guidelines for sports participation in competitive and recreational athletes with supraventricular arrhythmias and pacemakers. The question of imminent life-threatening arrhythmias is especially relevant when some form of ventricular rhythm disorder is documented, or when the patient is diagnosed to have inherited a pro-arrhythmogenic disorder. Frequent ventricular premature beats or nonsustained ventricular tachycardia may be a hallmark of underlying pathology and increased risk. Their finding should prompt a thorough cardiac evaluation, including both imaging modalities and electrophysiological techniques. This should allow distinguishing idiopathic rhythm disorders from underlying disease that carries a more ominous prognosis. Recommendations on sports participation in inherited arrhythmogenic conditions and asymptomatic gene carriers are also discussed: congenital and acquired long QT syndrome, short QT syndrome, Brugada syndrome, catecholaminergic polymorphic ventricular tachycardia, arrhythmogenic right ventricular cardiomyopathy and other familial electrical disease of unknown origin. If an implantable cardioverter defibrillator is indicated, it is no substitute for the guidelines relating to the underlying pathology. Moreover, some particular recommendations for patients/athletes with an implantable cardioverter defibrillator are to be observed.  相似文献   
59.
Primary linitis plastica of the rectum is an infrequent and unusual rectal carcinoma. We report a new case that presented clinically as a haemorrhoidal syndrome. We comment on the characteristics--clinical picture and histopathology--of this uncommon presentation of rectal tumour, as well as its clinical history and prognosis taking into account that the literature consulted indicated the unusualness of primary linitis plastica of the rectum.  相似文献   
60.
OBJECTIVE: Our goal was to evaluate thyroid function before and after surgery only or radiotherapy plus surgery for laryngeal neoplasms. STUDY DESIGN AND SETTING: The study group consisted of a total of 30 patients with laryngeal cancer (22 treated with surgery only and 8 treated with surgery plus radiotherapy) who were evaluated by ultrasensitive thyroid-stimulating hormone, free T4, and antithyroid antibodies both preoperatively and at 6 and 12 months after surgery. RESULTS: All patients had normal thyroid function before treatment (1 patient had elevated antithyroid autoantibodies); after 1 year, 4 (13.34%) patients were hypothyroid. In 3 patients, it was subclinical (ie, elevated thyroid-stimulating hormone with normal free T4), and in 1 patient, it was symptomatic. CONCLUSION: Our preliminary data suggest that hypothyroidism occurs in a small but substantial proportion of patients undergoing surgery with or without adjuvant radiotherapy for laryngeal cancer. SIGNIFICANCE: Thyroid hormone dosing should be routinely included in the assessment of patients with laryngeal cancer, because it is simple and inexpensive and may allow the early diagnosis and management of hypothyroidism.  相似文献   
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